
Universal Serial Bus Interface – On-The-Go Module
21-46
Freescale Semiconductor
21.4.4.1
USB On-Chip Transceiver Required External Components
USB system operation does not require external components. However, the recommended method ensures
driver output impedance, eye diagram, and V
BUS
cable fault tolerance requirements are met. The
recommended method is for the DM and DP I/O pads to connect through series resistors (approximately
33
Ω
each) to the USB connector on the application printed circuit board (PCB). Additionally, signal
quality optimizes when these 33
Ω
resistors are mounted close to the processor rather than closer to the
USB board level connector.
NOTE
Internal pull-down resistors are included that keep the DP and DM ports in
a known quiescent state when the USB port is not used or when a USB cable
is not connected.
Further, host operation requires 15k
Ω
external resistors to be connected
from DP and DM ports to ground. Device operation requires a 1.5k
Ω
pull-up resistor on DP (full-speed operation). The other end of this pull-up
resistor should be controlled by an open-drain, low impedence output pin
with a 3.3V I/O power supply. Readers are directed to section 7.1.5.1 of the
USB 2.0 specification.
21.5
Initialization/Application Information
21.5.1
Host Operation
Enhanced Host Controller Interface (EHCI) Specification defines the general operational model for the
USB modules in host mode. The EHCI specification describes the register-level interface for a host
controller for USB Revision 2.0. It includes a description of the hardware/software interface between
system software and host controller hardware. The next section has information about the initialization of
the USB modules; however, full details of the EHCI specification are beyond the scope of this document.
21.5.1.1
Host Controller Initialization
After initial power-on or module reset (via the USBCMD[RST] bit), all of the operational registers are at
default values, as illustrated in the register memory map in
.
Table 21-41. USB Network Speed and Required Physical Interface
USB Mode and Speed
DP and DN
On-Chip Analog
XCVR Active
I
2
C FEC
External Integrated Circuit Required
USB Host FS/LS
Yes
No
Yes See
Section 21.4.4.1, “USB On-Chip Transceiver
USB Device FS
Yes
No
Yes See
Section 21.4.4.1, “USB On-Chip Transceiver
Host/Device ULPI HS/FS
No
Yes
No
Maxim
MCF5329 Reference Manual, Rev 3
Содержание MCF5329
Страница 106: ...ColdFire Core 3 32 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 126: ...Enhanced Multiply Accumulate Unit EMAC 4 20 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 148: ...Cache 5 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 154: ...Static RAM SRAM 6 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 184: ...Power Management 8 18 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 204: ...Reset Controller Module 10 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 220: ...System Control Module SCM 11 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 228: ...Crossbar Switch XBS 12 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 268: ...General Purpose I O Module 13 40 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 392: ...SDRAM Controller SDRAMC 18 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 436: ...Fast Ethernet Controller FEC 19 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 564: ...Liquid Crystal Display Controller LCDC 22 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 594: ...FlexCAN 23 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 678: ...Pulse Width Modulation PWM Module 26 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 684: ...Watchdog Timer Module 27 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 692: ...Programmable Interrupt Timers PIT0 PIT3 28 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 704: ...DMA Timers DTIM0 DTIM3 29 12 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 720: ...Queued Serial Peripheral Interface QSPI 30 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 754: ...UART Modules 31 34 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 770: ...I2 C Interface 32 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 790: ...Message Digest Hardware Accelerator MDHA 33 20 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 866: ...Debug Module 36 50 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 902: ...Register Memory Map Quick Reference A 26 Freescale Semiconductor MCF5329 Reference Manual Rev 3...